1. Field of the Invention
The invention relates to a method of controlling the motions radiation source and a radiation detector, for example a film cassette, in relation to an adjusted slice position, for example a slice level, in a tomography apparatus without coupling rod, which tomography apparatus includes a table for accommodating an object, such as organ to be imaged by tomography. The invention also relates to a device for carrying out the method.
2. Description of the Related Art
Linear X-ray tomography of a slice or layer in a object has been performed for decades using a mechanically coupled source and film. Because of the recent introduction of (electronic) tomography without coupling rod, the mechanical pivot used thus far for mounting a light indicator for marking the adjusted slice position in the patient is no longer present. Since this location for mounting a light indicator no longer exists in electronic tomography, it is problematic for the X-ray technician to achieve exact adjustment of the position of the slice the patient.
EP 0 054 798 B1 discloses an adjusting unit for a radiation tomography apparatus. This construction includes a light beam detection device which is situated in line with a light beam generator, the horizontal line extending through the center of a region to be irradiated. The object to be irradiated is arranged on a height-adjustable table which is provided with a drive unit for raising and lowering. The data produced during the height adjustment of the table are electronically acquired and a control unit calculates a compare signal from the data acquired so as to store this signal for alignment of the horizontal line of the imaging region relative to the center of the part of the object to be imaged.